SEPA ENVIRONMENTAL CHECKLIST
Purpose of checklist:
Governmental agencies use this checklist to help determine whether the environmental impacts of your proposal are significant. This information is also helpful to determine if available avoidance, minimization or compensatory mitigation measures will address the probable significant impacts or if an environmental impact statement will be prepared to further analyze the proposal.
Instructions for applicants:
This environmental checklist asks you to describe some basic information about your proposal. Please answer each question accurately and carefully, to the best of your knowledge. You may need to consult with an agency specialist or private consultant for some questions. You may use “not applicable” or "does not apply" only when you can explain why it does not apply and not when the answer is unknown. You may also attach or incorporate by reference additional studies reports. Complete and accurate answers to these questions often avoid delays with the SEPA process as well as later in the decision- making process.
The checklist questions apply to all parts of your proposal, even if you plan to do them over a period of time or on different parcels of land. Attach any additional information that will help describe your proposal or its environmental effects. The agency to which you submit this checklist may ask you to explain your answers or provide additional information reasonably related to determining if there may be significant adverse impact.
Instructions for Lead Agencies: Please adjust the format of this template as needed. Additional information may be necessary to evaluate the existing environment, all interrelated aspects of the proposal and an analysis of adverse impacts. The checklist is considered the first but not necessarily the only source of information needed to make an adequate threshold determination. Once a threshold determination is made, the lead agency is responsible for the completeness and accuracy of the checklist and other supporting documents.
Use of checklist for nonproject proposals:
For nonproject proposals (such as ordinances, regulations, plans and programs), complete the applicable parts of sections A and B plus the SUPPLEMENTAL SHEET FOR NONPROJECT ACTIONS (part D). Please completely answer all questions that apply and note that the words "project," "applicant," and "property or site" should be read as "proposal," "proponent," and "affected geographic area," respectively. The lead agency may exclude (for non-projects) questions in Part B - Environmental Elements –that do not contribute meaningfully to the analysis of the proposal.
A. Background [HELP]
1. Name of proposed project, if applicable:
King County Harbor Island Dock Demolition
2. Name of applicant:
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King County Department of Natural Resources and Parks, Solid Waste Division
3. Address and phone number of applicant and contact person:
Applicant Stephanie Moller, Project Manager King County Department of Natural Resources and Parks, Solid Waste Division 201 S. Jackson Street, Suite 701 Seattle WA, 98104 (206)-263-0573
Applicant Representative Kate Snider, Floyd|Snider 601 Union Street, Suite 600 Seattle WA, 98101 (206) 292-2078
4. Date checklist prepared:
January 7, 2020
5. Agency requesting checklist:
King County Department of Natural Resources and Parks, Solid Waste Division
6. Proposed timing or schedule (including phasing, if applicable):
Construction is anticipated to begin in July 2021 and is anticipated to last approximately 8 months, with a tentative completion date of February 2022. The proposed project does not include phasing.
7. Do you have any plans for future additions, expansion, or further activity related to or connected with this proposal? If yes, explain.
The proposal is a standalone project initiated to meet the terms and conditions of an aquatic lease between the Washington Department of Natural Resources (DNR) and the King County Solid Waste Division (KCSWD).
8. List any environmental information you know about that has been prepared, or will be prepared, directly related to this proposal.
The following environmental information has been prepared directly to support the proposed project: • EHSI, Limited Hazardous Materials Survey Report, Harbor Island Dock Demolition Phase 1, July 2019 • EHSI, Phase 1 Environmental Site Assessment Report, Harbor Island Dock Demolition Phase 1, July 2019 • PanGEO, Preliminary Geotechnical Report, Harbor Island Dock Demolition Phase 1, August 2019
SEPA Environmental checklist (WAC 197-11-960) July 2016 Page 2 of 24 • Blue Coast Engineering, Coastal Engineering Report, Harbor Island Dock Demolition, September 2019 • Confluence, Biological Assessment, King County - Harbor Island Dock Demolition, January 2020
9. Do you know whether applications are pending for governmental approvals of other proposals directly affecting the property covered by your proposal? If yes, explain.
There are no known applications pending government approval at the project site.
10. List any government approvals or permits that will be needed for your proposal, if known.
The following government approvals and permits will be required for the proposed project: • U.S. Army Corps of Engineers: Department of Army Permit for Section 10 Work in Navigable Waters and Section 404 Discharge of Dredge or Fill Material • National Marine Fisheries Service (NMFS)/U.S. Fish and Wildlife Service (USFWS): Endangered Species Act (ESA) Section 7 Consultation • Washington State Department of Ecology (Ecology): Section 401 Water Quality Certification • Ecology: Coastal Zone Management Act Consistency Determination • Washington Department of Fish and Wildlife: Hydraulic Project Approval • City of Seattle: Shoreline Permit • City of Seattle: Construction Permits
11. Give brief, complete description of your proposal, including the proposed uses and the size of the project and site. There are several questions later in this checklist that ask you to describe certain aspects of your proposal. You do not need to repeat those answers on this page. (Lead agencies may modify this form to include additional specific information on project description.)
Project Purpose and Need
The KCSWD is proposing to demolish a derelict, creosote-treated timber dock located along the western shoreline of Harbor Island, at the mouth of the Duwamish River. The dock, which is approximately 72,700 square feet, has experienced a continuous state of decline while under the previous ownership of Fisher Mills and Pendleton Flour Mills during the 1990s and early 2000s. In 2003, the KCSWD purchased the upland mill site, which included the derelict dock structure; the conveyance of property deeds to the KCSWD included the assignment of DNR aquatic lease No. 22-002757, originally issued to Fisher Mills in 1992. The re-assignment of the DNR aquatic lease transferred the terms, conditions, and obligations of the original lease to the KCSWD. It is the KCSWD’s intent to maintain and renew this lease (set to expire on August 31, 2022) in order to retain marine access, which was a key reason for acquisition of the property.
The purpose of this project is to demolish and remove the remaining components of the derelict dock and leave the site in a stable condition, which would minimize potential for shoreline and sediment erosion. Completion of the project would meet obligations of the DNR aquatic lease. The DNR aquatic lease requires the Lessee to keep and maintain the property and improvements within the lease area in good order, repair, and condition, sufficient for safe use. In its current condition, the dock is beyond a state of repair; the derelict condition of the dock precludes any operational use of the structure. To fulfill the
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obligations of the DNR aquatic lease, the KCSWD seeks to demolish the dock to abate a hazard on the property and remove an inoperable structure. This work would be completed in a structurally sound manner to ensure the integrity of adjacent structures and would contribute to DNR’s creosote removal program efforts through removal of the existing creosote-treated piles associated with the derelict dock.
Project Description
The proposed project consists of the removal of an approximately 72,700-square-foot creosote-treated derelict dock structure, including its ancillary components, and shoreline stabilization work to stabilize the site once the derelict dock and associated components have been removed. A description of the proposed work is provided below, in the sequence that construction is anticipated to take place.
Dock Superstructure Demolition Project construction would begin with removal of the remaining dock superstructure, which is composed of timber decking, steel plates/sheets, timber stringers, timber pile caps, steel railroad tracks, and decommissioned steel sprinkler pipes. The removal of this structure would likely be conducted both from the uplands using a crane and/or excavator and from the water with floating equipment. Material removed from the dock superstructure would be stockpiled on site or on a debris barge, sorted for salvage, and disposed of at a Subtitle D landfill or recycled if deemed suitable for reuse.
Pile Removal Once the dock superstructure is demolished, the existing creosote-treated timber piles would be removed. There are approximately 1,800 creosote-treated piles in various states of deterioration at the project site. Piles within 30 feet of Warehouse E (as identified on the project plans) would be cut so that the piles remain below grade to preserve the warehouse’s structural integrity. All other piles would be fully extracted to the maximum extent feasible and disposed at a Subtitle D landfill. Due to the heavily deteriorated condition of the piles, a substantial number of piles would likely not be able to be fully extracted. If a pile breaks near or above the sediment surface during pile removal, multiple attempts to fully remove a creosote-treated pile using vibratory extraction, direct pull, or clamshell extraction would be taken before resorting to cutting. For piling that must be cut, piles located above Mean Lower Low Water (MLLW) would be cut 1 foot below mudline; piles located below MLLW would be cut at the mudline to minimize sediment disturbance. To the greatest extent possible, work between the Mean Higher High Water (MHHW) and MLLW would be conducted in the dry during low tide to minimize sediment disturbance.
Bulkhead/Concrete Foundation Removal and Upland Shoreline Stabilization The existing shoreline condition near and above MHHW consists of multiple discontinuous and failing concrete and CMU bulkheads, pile-supported concrete foundations, riprap revetment, and concrete rubble. The project includes removal of the existing concrete foundations and rubble by crane and/or excavator.
Once the derelict dock is removed, there is the potential for the existing failing bulkheads to be exposed to greater wave energy, which may accelerate their deterioration and result in further failure. Therefore, the existing vertical bulkheads (approximately 450 linear feet of bulkhead) would be demolished and replaced with a regraded riprap slope, while areas of existing riprap would be repaired or protected in place. The exception to this is along southern end of the shoreline adjacent to Warehouse E; an approximately 45- foot-long concrete bulkhead would be installed landward of the existing shoreline armoring to avoid excess of fill adjacent to the building (if there were to be no bulkhead, riprap would need to be placed at depths of approximately 6 feet deep in this area).Regrading of the shoreline is necessary in order to eliminate protrusions of the existing shoreline, which are currently vulnerable to scour. Ancillary to the upland shoreline stabilization work, an approximately 70-foot-long segment of existing 12-inch diameter
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stormwater outfall that would be disturbed during these activities would be replaced in-kind once regrading of the shoreline is complete.
Approximately 1,600 cubic yards of material would be regrading along the shoreline; approximately 1,000 cubic yards of riprap would be imported to replace the existing failing bulkheads and to repair areas of existing riprap. This work would be completed in the dry, from above the MHHW. The regraded shoreline would relocate the MHHW mark eastward in several locations, creating approximately 3,200 square feet of new aquatic area.
Surface Debris Removal and Sediment Stabilization Between MHHW and MLLW The sediment substrate beneath the dock between MHHW and MLLW is littered with miscellaneous building-material debris consisting of bricks, asphalt, concrete, and miscellaneous metal hardware. To remove this material, the proposed project would excavate the top 1 foot of debris-laden sediment within the footprint of the derelict dock structure above MLLW. A 1-foot-deep cover layer of 2.5-inch minus rounded gravel material would be immediately backfilled in excavated areas; any area subject to excavation would be backfilled within the same tide cycle to the greatest extent possible to minimize disturbance of sediments. To the greatest extent possible, work between MHHW and MLLW would be conducted at low tide, in the dry. Excavated sediment substrate/debris would be hauled off site and disposed of at a Subtitle D landfill. Approximately 1,000 cubic yards of debris-laden sediment would be removed from the site; approximately 1,000 cubic yards of 2.5-inch minus rounded gravel would be backfilled to stabilize the sediment and restore the existing elevations of the shoreline.
Surface Debris Removal and Sediment Stabilization Below the MLLW Large debris (such as wood beams, pipes, and steel plates) below MLLW would be removed by crane from a barge, with diver assistance, if necessary. Recovered debris would be stockpiled on site or on a debris barge, sorted for salvage, and disposed of at a Subtitle D landfill or recycled if deemed suitable for reuse. Following the removal of large surface debris, a 6-inch layer of coarse sand would be placed within the derelict dock footprint below MLLW to stabilize the substrate. Approximately 800 cubic yards of coarse sand would be placed to complete this work.
Sediment Sampling At the directive of the U.S. Environmental Protection Agency (USEPA), targeted sediment sampling would occur once the existing structures/piles and debris have been removed, but before placement of new substrates. The information gathered during the sediment sampling could influence future actions at the site but would not affect the proposed project.
12. Location of the proposal. Give sufficient information for a person to understand the precise location of your proposed project, including a street address, if any, and section, township, and range, if known. If a proposal would occur over a range of area, provide the range or boundaries of the site(s). Provide a legal description, site plan, vicinity map, and topographic map, if reasonably available. While you should submit any plans required by the agency, you are not required to duplicate maps or detailed plans submitted with any permit applications related to this checklist.
The project site includes aquatic land within the West Waterway of the Duwamish River, leased to King County by the DNR (Lease No. 22-002757), and King County-owned land immediately upland along the western shoreline of Harbor Island. The aquatic land leased to King County consists of three parcels (7666703025, 7666703030, and 7666703035); the upland King County-owned land is located on parcel 7666703020 and has a site address of 3235 16th Avenue Southwest in Seattle, Washington. The project site totals approximately 2.2 acres. Please see Attachment A for a vicinity map, Attachment B for a site plan, and Attachment C for a legal description of the parcels that comprise the project site.
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B. Environmental Elements [HELP]
1. Earth [help]
a. General description of the site:
The project site contains two distinct environments: the aquatic environment (portion of the project site located waterward of the MHHW) and the upland environment (portion of the project site located landward of the MHHW).
The aquatic portion of the project site is characterized by varying slopes, which slope downward toward the channel of the West Waterway of the Duwamish River to the west of the project site. Slopes between MHHW and MLLW range from approximately 10% to 50%; slopes below MLLW range from approximately 30% to 40%.
The upland environment is stabilized by an armored slope consisting of failing discontinuous bulkheads and intermittent sections of riprap and concrete rubble. Slopes associated with the armored section of the shoreline vary from approximately 10% to 40%. Landward of the existing armoring, the project site is generally flat.
(circle one): Flat, rolling, hilly, steep slopes, mountainous, other ______
The project site contains steep slopes attributed to the in-water elevations of a river channel and an engineered shoreline.
b. What is the steepest slope on the site (approximate percent slope)?
The steepest slopes within the project site are approximately 50%.
c. What general types of soils are found on the site (for example, clay, sand, gravel, peat, muck)? If you know the classification of agricultural soils, specify them and note any agricultural land of long-term commercial significance and whether the proposal results in removing any of these soils.
The project Geotechnical report describes Harbor Island as a man-made island constructed primarily from dredging the East and West Waterways located on the east and west sides of the island, respectively. The tideflat deposits generally consist of silt, sand, organic sediment and detritus with some shells associated with alluvial filling of the Duwamish valley. These soils are not suitable for agricultural use. d. Are there surface indications or history of unstable soils in the immediate vicinity? If so, describe.
According to the Seattle Department of Construction & Inspections GIS, the entire project site is located within a liquefaction-prone area. In addition, portions of the project site are mapped as steep slopes, primarily along the far west extent of the derelict dock superstructure, within the channel of the West Waterway of the Duwamish River. e. Describe the purpose, type, total area, and approximate quantities and total affected area of any filling, excavation, and grading proposed. Indicate source of fill.
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The proposed project would require filling and grading. Filling and grading would occur in both the aquatic and upland portions of the project site.
Uplands The upland portion of the project site would be regraded to smooth out the irregular shape of the shoreline to minimize the potential for scour. This would require the regrading of approximately 1,600 cubic yards over an area of about 10,100 square feet, (0.23 acre) near and above the MHHW. Once the shoreline has been regraded to the proposed configuration, approximately 1,000 cubic yards of riprap would be imported to replace the existing failing bulkheads and to repair areas of existing riprap. Filling (placement of riprap) would occupy approximately 6,300 square feet of the regraded shoreline slope, which is consistent with the footprint of the existing armoring.
Aquatic Excavation would occur below the MHHW to remove existing debris that has been intermixed in the sediment within the footprint of the derelict dock structure. Excavation would consist of removing the top 1-foot layer of debris-laden sediment within the footprint of the derelict dock structure between the MHHW and the MLLW. It is anticipated that approximately 1,000 cubic yards of debris-laden sediment would be removed (approximately 30,000 square feet (0.69 acres) of area would be affected). The removed materials would be replaced in situ with approximately 1,000 cubic yards of 2.5-inch minus rounded gravel. Below MLLW, approximately 800 cubic yards of coarse sand material would be evenly distributed within the footprint of the derelict dock structure (an area of approximately 41,000 square feet, or 0.94 acre), resulting in an approximately 6-inch layer of material, which would stabilize the sediments below MLLW once the dock has been removed. In addition, approximately 200 square feet (0.004 acre) of riprap would be repaired near and slightly below MHHW at the south end of the project site. f. Could erosion occur as a result of clearing, construction, or use? If so, generally describe.
During construction, excavation/grading above and below MHHW has the potential to result in erosion because the existing soil/sediment conditions would be disturbed. However, the contractor will implement the best management practices (BMPs) identified in the response to question B.1.h to minimize this potential.
Once project construction is complete, the project would not significantly contribute to erosion potential. The project design includes smoothing of the irregularly shaped shoreline, shoreline armoring replacement/repair, and sediment stabilization measures that would minimize erosion potential at the site after the derelict dock structure has been removed. These project elements were specifically incorporated into project design to minimize erosion potential at the site. g. About what percent of the site will be covered with impervious surfaces after project construction (for example, asphalt or buildings)?
The proposed project would not result in an increase of impervious surfaces at the site. h. Proposed measures to reduce or control erosion, or other impacts to the earth, if any:
The following BMPs will be implemented by the contractor to reduce the potential for impacts to the earth during construction, which could include increased erosion/turbidity:
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• A Temporary Soil Erosion Control Plan will be implemented, to minimize potential for erosion. The Soil Erosion Control Plan will include stockpile management BMP’s such as lined containment cells constructed of concrete ecology blocks that will serve to manage the temporary stockpiling and sorting of debris materials. Temporary containment cells will be located on the uplands above the highest observed tide conditions. Drainage from the containment cells will be sloped away from the shoreline and will be collected in holding tanks for proper disposal. Storm water runoff not requiring special disposal will be filtered through coir bundles, straw wattles or similar approved BMPS’s, and monitored for acceptable turbidity before discharge to the site storm drainage system. • Between MHHW and MLLW, pile removal and debris-laden sediment removal would occur in the dry to the greatest extent possible. • Once debris-laden sediment is removed, the disturbed area would be immediately backfilled to stabilize the exposed sediments. This would occur in one tide cycle to the greatest extent possible. • A vibratory hammer and the proposed pile cut-off depths would be utilized during pile removal to minimize disturbance to sediments. • Shoreline regrading and riprap repair will be performed in the dry during low tide with a land- based excavator or crane to the greatest extent possible.
In addition, as stated in response to question B.1.f, the project design includes smoothing of the irregularly shaped shoreline, replacement/repair of shoreline armoring, and sediment stabilization measures specifically to minimize and control erosion at the site.
2. Air [help]
a. What types of emissions to the air would result from the proposal during construction, operation, and maintenance when the project is completed? If any, generally describe and give approximate quantities if known.
During construction, construction equipment and vehicle traffic may generate particle pollution from dust and emissions that includes nitrogen oxides (NOx), carbon monoxide (CO), and PM10 (dust), but this pollution would be temporary in nature and negligible in quantity.
A King County greenhouse gas emissions worksheet has not been prepared for this project. King County’s greenhouse gas emissions worksheet apply to construction projects that build or establish a new use or structure, and for projects that lay pavement. The proposed project activities are outside of the purview of the King County greenhouse gas emission worksheet and is therefore not included. b. Are there any off-site sources of emissions or odor that may affect your proposal? If so, generally describe.
There are no sources of offsite emissions or odors that would affect the proposed project. c. Proposed measures to reduce or control emissions or other impacts to air, if any:
During construction, impacts to air quality would be reduced and controlled through implementation of standard federal, state, and local emission control criteria and City of Seattle construction practices. These would include requiring the contractor to use the best available control technologies, proper vehicle maintenance, and minimizing vehicle and equipment idling.
3. Water [help]
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a. Surface Water: [help]
1) Is there any surface water body on or in the immediate vicinity of the site (including year-round and seasonal streams, saltwater, lakes, ponds, wetlands)? If yes, describe type and provide names. If appropriate, state what stream or river it flows into.
The proposed project would require work within and adjacent to the West Waterway of the Duwamish River, which is classified as a Type-S waterbody by the DNR.
2) Will the project require any work over, in, or adjacent to (within 200 feet) the described waters? If yes, please describe and attach available plans.
Yes. The entire project, as described in response to question A.11, would occur either within or directly adjacent to the West Waterway of the Duwamish River. Please see Attachment B for the proposed project’s site plan.
3) Estimate the amount of fill and dredge material that would be placed in or removed from surface water or wetlands and indicate the area of the site that would be affected. Indicate the source of fill material.
The following fill/excavation activities would occur waterward of the MHHW of the West Waterway of the Duwamish River.
Excavation Although dredging would not occur, the project includes excavation below MHHW within the footprint of the derelict dock structure; this work would be conducted in the dry to the greatest extent possible. The excavation work includes removal of the top 1 foot of sediment between MHHW and MLLW to remove debris in sediment that has accumulated over time due to the deteriorating condition of the dock. Approximately 1,000 cubic yards of debris-laden sediment would be removed.
Fill/Imported Materials Approximately 1,000 cubic yards of fill (2.5-inch minus rounded gravel) would be placed as backfill where debris-laden sediment removal would occur. The purpose of this fill material is to stabilize exposed sediments after excavation and to restore the existing elevations of the shoreline. Below MLLW, approximately 800 cubic yards of coarse sand material would be placed (to a depth of approximately 6 inches) within the outermost portion of the footprint of the existing dock superstructure to stabilize sediments after pile and debris removal. In addition, approximately 200 square feet of riprap will be repaired near the MHHW mark at the south end of the project site. Imported materials would be sourced from an approved local quarry meeting the project specifications for the material.
4) Will the proposal require surface water withdrawals or diversions? Give general description, purpose, and approximate quantities if known.
The proposed project would not require surface water withdrawals or diversions.
5) Does the proposal lie within a 100-year floodplain? If so, note location on the site plan.
The project site is located within the Federal Emergency Management Agency’s Flood Insurance Rate Map (FIRM) Panel 53033C0630F, which designates the upland site as Zone X (areas
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determined to be outside 500-year floodplain). The dock structure is located along the existing shoreline and lies within a portion of the Duwamish River floodway. The proposed work is to remove the dock structure from the shoreline and the floodway which will result in beneficial effects on flood-flow characteristics.
6) Does the proposal involve any discharges of waste materials to surface waters? If so, describe the type of waste and anticipated volume of discharge.
The proposed project does not include discharge of waste material into surface waters. b. Ground Water: [help]
1) Will groundwater be withdrawn from a well for drinking water or other purposes? If so, give a general description of the well, proposed uses and approximate quantities withdrawn from the well. Will water be discharged to groundwater? Give general description, purpose, and approximate quantities if known.
The proposed project would not withdraw groundwater for any purpose. In addition, no water would be discharged to groundwater sources.
2) Describe waste material that will be discharged into the ground from septic tanks or other sources, if any (for example: Domestic sewage; industrial, containing the following chemicals. . . ; agricultural; etc.). Describe the general size of the system, the number of such systems, the number of houses to be served (if applicable), or the number of animals or humans the system(s) are expected to serve.
The proposed project would not discharge waste material into the ground. c. Water runoff (including stormwater):
1) Describe the source of runoff (including storm water) and method of collection and disposal, if any (include quantities, if known). Where will this water flow? Will this water flow into other waters? If so, describe.
Stormwater is generated within the upland area of the project site during rain events. Stormwater in the upland area is collected and treated by an electrocoagulation system prior to discharge to a 12-inch-diameter concrete outfall that is located within the footprint of the existing derelict dock superstructure. The proposed project would not introduce new sources of stormwater runoff or alter the existing stormwater facilities at the site. The stormwater outfall that currently lies within the footprint of the derelict dock structure would be protected in place.
2) Could waste materials enter ground or surface waters? If so, generally describe.
The proposed project would not introduce new sources of stormwater or alter existing stormwater management facilities. In addition, BMPs (as described in response to question B.h.1) will be implemented by the contractor to minimize the potential for erosion. Therefore, the proposed project would not increase the potential for waste materials to enter groundwater or surface waters.
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3) Does the proposal alter or otherwise affect drainage patterns in the vicinity of the site? If so, describe.
The proposed project would not add or remove existing impervious surface or otherwise alter the existing drainage patterns at the site. d. Proposed measures to reduce or control surface, ground, and runoff water, and drainage pattern impacts, if any:
To ensure that the project does not result in stormwater runoff impacts, the existing outfall within the footprint of the derelict dock structure would be protected in place. In addition, the erosion control measures described in response to question B.h.1 will be implemented by the contractor to ensure that debris-laden water does not run off to the West Waterway of the Duwamish River during project construction.
4. Plants [help]
a. Check the types of vegetation found on the site:
____ deciduous tree: alder, maple, aspen, other __X_ evergreen tree: fir, cedar, pine, other: Madrone __X_ shrubs ____ grass ____ pasture ____ crop or grain ____ Orchards, vineyards or other permanent crops. ____ wet soil plants: cattail, buttercup, bullrush, skunk cabbage, other __X_ water plants: water lily, eelgrass, milfoil, other: Rockweed and Sea lettuce ____ other types of vegetation
The existing vegetation within the project site is limited due to the past and present industrial activities at and within the vicinity of the project site. Upland vegetation is limited to a narrow swath of intermittent shrubs (blackberry and butterfly bush [considered invasive/noxious]) and a tree (madrone) that have grown through sections of the derelict dock and gaps between the existing sections of intermittent hard shoreline armoring.
Similar to the upland area, existing vegetation within the aquatic portion of the project site is limited due to past and present industrial practices and includes intermittent locations of rockweed and sea lettuce.
b. What kind and amount of vegetation will be removed or altered?
Project construction would require removal of the limited vegetation within the project site in the upland area and in the aquatic area between MHHW and MLLW where rockweed and sea lettuce is attached to the building material debris such as concrete rubble, asphalt, and bricks. Rockweed and sea lettuce that is attached to existing riprap to be protected-in-place would remain undisturbed to the maximum extent feasible
c. List threatened and endangered species known to be on or near the site.
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No threatened or endangered plant species have been identified or are known to occur at or within the vicinity of the project site. d. Proposed landscaping, use of native plants, or other measures to preserve or enhance vegetation on the site, if any:
The proposed project does not include a landscaping or vegetation preservation/enhancement component. e. List all noxious weeds and invasive species known to be on or near the site.
A majority of the limited vegetation at the project site includes invasive/noxious plant species. This includes the Himalayan blackberry (Rubus armeniacus) and butterfly bush (Buddleja davidii).
5. Animals [help] a. List any birds and other animals which have been observed on or near the site or are known to be on or near the site.
Examples include:
birds: hawk, heron, eagle, songbirds, other: Marbled murrelet, Canada Goose, Western Gull mammals: deer, bear, elk, beaver, other: California and Steller Sea Lion fish: bass, salmon, trout, herring, shellfish, other: Cetaceans
The project site is located within and adjacent to the West Waterway of the Duwamish River. Although environmental conditions at the project site are heavily degraded due to the past industrial use at the site and current ongoing industrial operations in the surrounding area, the Duwamish River remains an important habitat for resident marine/estuarine and anadromous fish including several salmonid species. b. List any threatened and endangered species known to be on or near the site.
ESA-listed species that could utilize the habitat within the West Waterway of the Duwamish River or occur within the vicinity of the project site include the following: • Bull trout (Salvelinus confluentus) • Chinook salmon (Oncorhynchus tshawytscha) • Steelhead (Oncorhynchus mykiss) • Bocaccio rockfish (Sebastes paucispinis) • Yelloweye rockfish (Sebastes ruberrimus) • Killer whale (Orcinus orca) • Humpback whale (Megaptera novaeangliae) • Marbled murrelet (Brachyramphus marmoratus) c. Is the site part of a migration route? If so, explain.
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Yes. The general project area is located within the Pacific Flyway, a broad migratory corridor that extends from Alaska to South America, which is used by waterfowl, eagles, hawks, falcons, songbirds, and shorebirds. In addition, the project site is located within and adjacent to the West Waterway of the Duwamish River, which is utilized by several salmonid species as a migratory corridor. d. Proposed measures to preserve or enhance wildlife, if any:
The regraded shoreline would shift the MHHW mark east in several locations, creating approximately 3,200 square feet of new aquatic area.
In addition, BMPs will be implemented by the contractor to minimize/avoid impacts to wildlife and their environs during construction. This includes but is not limited to the following: • In-water work will occur within the approved in-water work window to minimize impacts to migrating juvenile salmonids. • Work will be done during low tide and in the dry to the greatest extent possible to minimize potential for sediment discharge to the waterway. • During all in-water or overwater work, containment booms and absorbent booms will be deployed around the work area to contain any floatable debris or spills that may enter the waterway and manage sheens that may result from pile-pulling activities. • A vibratory hammer will be utilized to the maximum extent feasible during pile removal to minimize disturbance to sediments. • Piles located below MLLW that are deteriorated to the point that they cannot be fully extracted will be cut off at the mudline to minimize sediment disturbance. • Excavation of the debris-laden sediment and backfill will be conducted in the same tidal cycle to the greatest extent possible to minimize resuspension of sediment as tides change. • Shoreline regrading and riprap placement will be performed in the dry during low tide with land-based equipment to minimize sediment disturbance.
e. List any invasive animal species known to be on or near the site.
There are no known invasive species that occur at or near the project site.
6. Energy and Natural Resources [help]
a. What kinds of energy (electric, natural gas, oil, wood stove, solar) will be used to meet the completed project's energy needs? Describe whether it will be used for heating, manufacturing, etc.
The completed project would not require the use of energy or other natural resources. b. Would your project affect the potential use of solar energy by adjacent properties? If so, generally describe.
The proposed project does not include the construction of vertical elements that could impact adjacent properties’ ability to use solar energy.
SEPA Environmental checklist (WAC 197-11-960) July 2016 Page 13 of 24 c. What kinds of energy conservation features are included in the plans of this proposal? List other proposed measures to reduce or control energy impacts, if any:
Because the completed project would not utilize energy/natural resources, no conservation measures are required or proposed.
7. Environmental Health [help] a. Are there any environmental health hazards, including exposure to toxic chemicals, risk of fire and explosion, spill, or hazardous waste, that could occur as a result of this proposal? If so, describe.
A Limited Hazardous Materials Survey of the derelict dock was performed by EHSI to identify and quantify asbestos-containing building materials (ACM) and lead-containing materials (LCM) that may be impacted by the project. The survey found limited quantities of ACM material in pipes from a former fire protection sprinkler system, asphaltic cloth between some of the piles and pile caps and a small remnant cement asbestos board from a previous building that was located on the dock. LCM was found in the coating of the former sprinkler piping. Piles are treated with creosote. Guidelines and requirements for handling of hazardous demolition materials will conform to the project Hazardous Materials Survey and BMP’s. Removal of these materials would benefit the aquatic environment.
The project does not include operations or activates with the potential to produce hazardous materials. However, equipment used to perform the demolition work may include potentially hazardous materials in the form of gasoline and diesel fuels, hydraulic fluids, oils, and lubricants. These materials will be subject to local, state and federal controls and regulations pertaining to use, handling and storage.
1) Describe any known or possible contamination at the site from present or past uses.
The aquatic portion of the project site is within the boundaries of the West Waterway Operable Unit of the Harbor Island Superfund Site; therefore, it is possible that contaminated sediment may be present within the boundaries of the project site. In addition, the upland portion of the project site is within the boundaries of the Soil and Groundwater Operable Unit of the Harbor Island Superfund Site, although there is no known contamination in the project area. The project site also contains approximately 1,800 deteriorating creosote-treated timber piles and creosote-treated timber structural components of the derelict dock structure as well as associated debris. These piles, remaining structural components of the derelict dock, and debris would be removed as part of this proposed project.
2) Describe existing hazardous chemicals/conditions that might affect project development and design. This includes underground hazardous liquid and gas transmission pipelines located within the project area and in the vicinity.
As described in response to question 7.a, a Limited Hazardous Materials survey found limited quantities of asbestos-containing building materials (ACM) and lead-containing materials (LCM). These materials will be removed and properly disposed as part of the project. There are no other known existing hazardous chemicals/conditions within the project site that could affect project development.
3) Describe any toxic or hazardous chemicals that might be stored, used, or produced
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during the project's development or construction, or at any time during the operating life of the project.
Fossil fuels may be stored at the site during project construction so construction equipment can be refueled. The completed project would not result in the storage, use, or production of any toxic or hazardous substance.
4) Describe special emergency services that might be required.
The proposed project would not require the use of special emergency services.
5) Proposed measures to reduce or control environmental health hazards, if any: The primary purpose of the proposed project is to demolish and remove the remaining components of a creosote-treated derelict dock structure and associated materials that have littered the substrates within its footprint. As part of the demolition process, the remaining portions of the dock structure, including approximately 1,800 creosote-treated piles, would be removed from the West Waterway of the Duwamish River. In addition, within the derelict dock’s footprint between MHHW and MLLW, the top 1 foot of debris-laden sediment would be excavated and removed. Unsalvageable pieces of the dock structure, the creosote-treated piles, debris that has separated from the derelict dock, and excavated debris-laden sediment would be disposed of at a Subtitle D landfill. This work would remove creosote-treated material from the West Waterway of the Duwamish River.
At the directive of USEPA, targeted sediment sampling would occur once the existing structures/piles and debris have been removed, but before placement of new substrates. The information gathered during the sediment sampling could influence future actions at the site but would not affect the proposed project. b. Noise
1) What types of noise exist in the area which may affect your project (for example: traffic, equipment, operation, other)?
The proposed project is not noise sensitive; therefore, no noise sources would negatively impact the proposal.
2) What types and levels of noise would be created by or associated with the project on a short-term or a long-term basis (for example: traffic, construction, operation, other)? Indicate what hours noise would come from the site.
The proposed project would result in only a temporary short-term increase in noise during project construction. This noise would remain consistent with the ambient industrial noise in the area. It is anticipated that noise produced by project construction would occur between 7 a.m. and 10 p.m. during weekdays and 9 a.m. and 10 p.m. during weekends, consistent with the City of Seattle noise ordinance. Limited periods of night work may be required due to tidal conditions.
3) Proposed measures to reduce or control noise impacts, if any:
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The proposed project would not result in adverse noise impacts; therefore, noise reduction and control measures are not included in the proposal.
8. Land and Shoreline Use [help]
a. What is the current use of the site and adjacent properties? Will the proposal affect current land uses on nearby or adjacent properties? If so, describe.
The aquatic portion of the project site is not currently in use because it contains a derelict dock structure that has not been operational in over two decades. The upland portion of the project site abuts an active industrial bulk shipping use. b. Has the project site been used as working farmlands or working forest lands? If so, describe. How much agricultural or forest land of long-term commercial significance will be converted to other uses as a result of the proposal, if any? If resource lands have not been designated, how many acres in farmland or forest land tax status will be converted to nonfarm or nonforest use?
The project site is a man-made island constructed of dredge materials from the West Waterway and has no historic agricultural or silvicultural use.
1) Will the proposal affect or be affected by surrounding working farm or forest land normal business operations, such as oversize equipment access, the application of pesticides, tilling, and harvesting? If so, how:
No. There are no working farm or forest land operations in the vicinity of the project site.
c. Describe any structures on the site.
The project site contains a derelict dock structure approximately 72,700 square feet in size and ancillary components. There is also a 12-inch-diameter concrete stormwater outfall underneath the dock structure and a security fence that parallels the shoreline. An existing pile supported warehouse structure is located at the south end of the dock. The warehouse structure would be protected-in-place and would remain after dock demolition. The upland site includes various buildings and storage silos that would be unaffected by the project.
d. Will any structures be demolished? If so, what?
The purpose of the proposed project is to demolish the remaining components of a derelict dock structure and stabilize the shoreline once the structure/materials have been removed. The proposed demolition work would consist of the following: • Demolition of the remaining dock superstructure, which consists of steel plates/sheets, timber decking, timber stringers, timber pile caps, steel railroad tracks, and decommissioned steel sprinkler pipes. • Removal of approximately 1,800 creosote-treated piles. • Removal of the discontinuous bulkheads, concrete foundations, and concrete rubble at or around MHHW.
e. What is the current zoning classification of the site?
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The project site is located within the City of Seattle’s Industrial General 1 (IG1) zone. f. What is the current comprehensive plan designation of the site?
The project site contains a Greater Duwamish Manufacturing/Industrial Center comprehensive plan designation. g. If applicable, what is the current shoreline master program designation of the site?
The project site contains an Urban Industrial (UI) shoreline master program designation. h. Has any part of the site been classified as a critical area by the city or county? If so, specify.
According to the Seattle Department of Construction & Inspections GIS, the project site contains the following environmentally critical areas: • Steep slopes • Liquefaction-prone area • Wildlife habitat
i. Approximately how many people would reside or work in the completed project?
The proposed project is a demolition/shoreline stabilization project. No one would reside or work at the project site as it relates to this proposal.
j. Approximately how many people would the completed project displace?
The proposed project would not result in the displacement of people.
k. Proposed measures to avoid or reduce displacement impacts, if any:
No displacement impacts would occur; therefore, displacement avoidance or reduction measures are not required or proposed.
L. Proposed measures to ensure the proposal is compatible with existing and projected land uses and plans, if any:
This demolition/shoreline stabilization project would not result in compatibility impacts with current or future land uses; this would be verified by the City of Seattle when permits for the project are applied for.
m. Proposed measures to reduce or control impacts to agricultural and forest lands of long-term commercial significance, if any:
The proposed project would not result in adverse impact to agricultural or forest lands of long-term commercial significance; therefore, impact reduction and control measures are not proposed.
9. Housing [help]
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a. Approximately how many units would be provided, if any? Indicate whether high, middle, or low-income housing.
The proposed project would not create new housing. b. Approximately how many units, if any, would be eliminated? Indicate whether high, middle, or low-income housing.
The proposed project would not eliminate existing housing. c. Proposed measures to reduce or control housing impacts, if any:
No housing impacts would occur; therefore, no impact reduction or control measures are proposed.
10. Aesthetics [help] a. What is the tallest height of any proposed structure(s), not including antennas; what is the principal exterior building material(s) proposed?
An approximately 45-foot-long concrete replacement bulkhead would be constructed above the MHHW near Warehouse E to minimize the amount of imported riprap that would be placed to protect the adjacent building. This structure would be constructed at grade. No other buildings or structures are proposed.
b. What views in the immediate vicinity would be altered or obstructed?
The removal of the derelict dock structure and appurtenances would improve the views along the West Waterway of the Duwamish River and from Terminal 5, when looking east. c. Proposed measures to reduce or control aesthetic impacts, if any:
The proposed project would not result in adverse aesthetic impacts; rather, the aesthetics of the area would be improved through removal of the derelict dock structure and appurtenances.
11. Light and Glare [help]
a. What type of light or glare will the proposal produce? What time of day would it mainly occur?
During project construction light/glare could be temporarily produced when work coincides with low light conditions. The completed project would not produce light or glare.
b. Could light or glare from the finished project be a safety hazard or interfere with views?
The completed project would not result in light or glare impacts.
c. What existing off-site sources of light or glare may affect your proposal?
The proposed project would not be affected by existing offsite sources of light or glare.
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d. Proposed measures to reduce or control light and glare impacts, if any:
The proposed project would not result in light or glare impacts; therefore, light/glare reduction or control measures are not proposed.
12. Recreation [help] a. What designated and informal recreational opportunities are in the immediate vicinity?
Within the vicinity of the project site, the nearest formally designated recreational opportunity is the Terminal 18 Park located approximately 1,200 feet to the southeast. Informal recreation opportunities within the vicinity of the project site are limited to the West Waterway of the Duwamish River, which provides water-based recreational opportunities to the industrial area that the project site is located within. b. Would the proposed project displace any existing recreational uses? If so, describe.
The proposed project would not displace any existing recreational uses. c. Proposed measures to reduce or control impacts on recreation, including recreation opportunities to be provided by the project or applicant, if any:
The proposed project would not result in recreational impacts; therefore, no impact reduction or control measures are required or proposed.
13. Historic and cultural preservation [help]
a. Are there any buildings, structures, or sites, located on or near the site that are over 45 years old listed in or eligible for listing in national, state, or local preservation registers ? If so, specifically describe.
The derelict dock structure within the project site is over 45 years old; however, the structure is not listed as eligible for listing in the Washington Department of Archaeology and Historic Preservation (DAHP) inventory and is currently in ruin.
According to DAHP’s Washington Information System for Architectural & Archaeological Records Data (WISAARD), Fisher Flouring Mills, which is located within the project area, is over 45 years old; however, a determination regarding its state listing eligibility has not been made.
b. Are there any landmarks, features, or other evidence of Indian or historic use or occupation? This may include human burials or old cemeteries. Are there any material evidence, artifacts, or areas of cultural importance on or near the site? Please list any professional studies conducted at the site to identify such resources.
The project site is located on Harbor Island, which is an artificial island created at the mouth of Duwamish River through placement of fill in the early 20th century. As such, the land which the project site is located on has not been occupied by Tribes or been subject to other historic occupation. c. Describe the methods used to assess the potential impacts to cultural and historic resources on or near the project site. Examples include consultation with tribes and the department of archeology and historic preservation, archaeological surveys, historic maps, GIS data, etc.
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Desktop resources such as DAHP’s WISAARD tool were referenced to assess the presence of cultural or historic resources are the project site. d. Proposed measures to avoid, minimize, or compensate for loss, changes to, and disturbance to resources. Please include plans for the above and any permits that may be required.
The proposed project would limit demolition activities to the derelict dock structure and appurtenant components; adjacent structures would remain unaltered. Ground-disturbing activities would occur within the top approximately 1 foot of accumulated sediment within the West Waterway of the Duwamish River’s channel, or on Harbor Island; these sources would not contain culturally significant sites because they are either sediment (river channel) or fill (Harbor Island).
14. Transportation [help] a. Identify public streets and highways serving the site or affected geographic area and describe proposed access to the existing street system. Show on site plans, if any.
The project site can be accessed via 16th Avenue SW, located approximately 450 feet to the east. Please see the project’s vicinity map (Attachment A) for more details. b. Is the site or affected geographic area currently served by public transit? If so, generally describe. If not, what is the approximate distance to the nearest transit stop?
The geographic area (Harbor Island) is not served by public transit. c. How many additional parking spaces would the completed project or non-project proposal have? How many would the project or proposal eliminate?
The proposed project does not include the construction or removal of parking spaces. d. Will the proposal require any new or improvements to existing roads, streets, pedestrian, bicycle or state transportation facilities, not including driveways? If so, generally describe (indicate whether public or private).
The proposed project does not include improvements to existing public transportation routes or facilities. e. Will the project or proposal use (or occur in the immediate vicinity of) water, rail, or air transportation? If so, generally describe.
The project site is located adjacent to water and rail transportation. The West Waterway of the Duwamish River provides a water transportation route for many industrial operations in the area; Seattle Bulk Shipping is located within the project site/project area and is served by rail. Both water-borne and rail transportation may be utilized for transportation of waste materials from the project site or for provision of imported substrate materials. f. How many vehicular trips per day would be generated by the completed project or proposal? If known, indicate when peak volumes would occur and what percentage of the volume would
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be trucks (such as commercial and nonpassenger vehicles). What data or transportation models were used to make these estimates?
No vehicular trips would be generated by the completed project.
g. Will the proposal interfere with, affect or be affected by the movement of agricultural and forest products on roads or streets in the area? If so, generally describe.
The proposed project would not interfere with or affect the movement of agricultural and forest products. h. Proposed measures to reduce or control transportation impacts, if any:
The proposed project would not result in transportation impacts; therefore, transportation impact reduction or control measures are not proposed.
15. Public Services [help]
a. Would the project result in an increased need for public services (for example: fire protection, police protection, public transit, health care, schools, other)? If so, generally describe.
The proposal is for a demolition/shoreline stabilization project; public services would not be required as result of project completion.
b. Proposed measures to reduce or control direct impacts on public services, if any.
The proposed project would not result in impacts to public services; therefore, impact control or reduction measures are not proposed.
16. Utilities [help]
a. Circle utilities currently available at the site: electricity, natural gas, water, refuse service, telephone, sanitary sewer, septic system, other ______
The utilities circled above serve the upland parcel associated with the project site; however, the completed project would not require use of these utilities. b. Describe the utilities that are proposed for the project, the utility providing the service, and the general construction activities on the site or in the immediate vicinity which might be needed.
The proposal is for a demolition/shoreline stabilization project; utilities would not be required for the completed project.
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Attachment 1 – Vicinity Map KING COUNTY SOLID WASTE DIVISION HARBOR ISLAND DOCK DEMOLITION SEATTLE, WASHINGTON (PRELIMINARY DESIGN)
PUGET SOUND SEE LOCATION MAP
HARBOR ISLAND
PORT OF SEATTLE TERMINAL 5 WEST WATERWAY DUWAMISH RIVER PROJECT SITE HWY 99
WEST SEATTLE BRIDGE
LOCATION MAP FOR CONCEPTUAL PLANNING PURPOSES ONLY VICINITY MAP DO NOT USE FOR CONSTRUCTION KCSWD HARBOR ISLAND DOCK DEMO 3235 16TH AVE SW, SEATTLE, WASHINGTON
1601 5th Avenue, Suite 1300 VICINITY MAP Seattle, Washington 98101 King County FIGURE 1
(206) 382-0600 Fax (206) 382-0500 PRELIMINARY DESIGN
Attachment 2 – Site Plan Know what's below. NOTES 1601 5th Avenue, Suite 1300 (206) 382-0600 Fax 382-0500 Seattle, Washington 98101 Call before you dig.
R
INNER HARBOR LINE HARBOR INNER OUTER HARBOR LINE HARBOR OUTER King County
1474
524
1475
1478
1477
1476
1479 1481 DUWAMISH RIVER WEST WATERWAY
1480 FOR CONCEPTUAL PLANNING PURPOSES ONLY DO NOT USE FOR CONSTRUCTION KCSWD HARBOR ISLAND DOCK DEMO 3235 16TH AVE SW, SEATTLE, WASHINGTON EXISTING CONDITIONS SITE PLAN PROPOSED DOCK DEMOLITION LEGEND AND FIGURE 2
N
PRELIMINARY DESIGN LEGEND
”
”
INNER HARBOR LINE
OUTER HARBOR LINE N R WEST WATERWAY DUWAMISH RIVER
Know what's below. FOR CONCEPTUAL PLANNING PURPOSES ONLY Call before you dig. DO NOT USE FOR CONSTRUCTION KCSWD HARBOR ISLAND DOCK DEMO 3235 16TH AVE SW, SEATTLE, WASHINGTON
1601 5th Avenue, Suite 1300 PROPOSED DEVELOPED CONDITIONS SITE PLAN Seattle, Washington 98101 King County FIGURE 3
(206) 382-0600 Fax (206) 382-0500 PRELIMINARY DESIGN
Attachment 3 – Legal Descriptions
Parcel 7666703025: SEATTLE TIDE LDS EXT # 1 LEASE WP 116 AREA 21213 M/L STL 407 FRONT LOTS 1-2 IN WEST WATERWAY TAXABLE THROUGH PERSONAL PROPERTY
Parcel 7666703030: SEATTLE TIDE LDS EXT # 1 LEASE WP 109 AREA 31820 M/L STL 407 FRONT LOTS 3-4-5 IN WEST WATERWAY TAXABLE THROUGH PERSONAL PROPERTY
Parcel 7666703035: SEATTLE TIDE LDS EXT # 1 LEASE WP 110 AREA 26764 M/L STL 407 FRONT LOTS 6-7-8 IN WEST WATERWAY TAXABLE THROUGH PERSONAL PROPERTY
Parcel 7666703020: SEATTLE TIDE LDS EXT #1 & POR VAC SW HANFORD ST ADJ TGW THAT POR OF VAC CHELAN AVE SW ADJ SD LOTS - VAC UNDER C.O.S. ORD NO 121123 AND REC UNDER REC NO 20030606000283
Legal Descriptions Page 1